Beds generally, and hospital beds in particular have recently been undergoing a design transformation. Early beds were very basic devices providing limited support and care features. More recently, bed designs have been taking advantage of technological developments to provide improvements in bed articulation, mattress inflation, patient access, convenience and control.
Inflatable mattress cushions or cells in such beds are often connected to a support surface of a base platform or frame. These connections may be provided by a connector having an inner channel or passageway, that attaches the cell to a port extending through the support surface. Further, it is known to connect two cells together with a passageway formed in the connection to allow air to flow between the connected cells. An example of such an arrangement is disclosed by Pertchik in U.S. Pat. No. 4,255,824 for "Cushion for Decubitus Ulcers". Pertchik discloses a cushion for sitting formed of a plurality of elongate cells that are connected at contact points to provide inflation of all the cells from a single inlet.
Various forms of cushions and mattresses have been designed in order to provide improved support for a patient. Viesturs et al., in U.S. Pat. No. 4,534,078 entitled "Body Supporting Mattress", disclose an elongate inner cell supported on a pad having a peripheral inflated tube. Generally U-shaped cells that alternate and are offset for use in turning a patient are disclosed in U.S. Pat. No. 5,003,654 issued to Vrzalik for a "Method and Apparatus for Alternating Pressure of a Low Air Loss Patient Support System". In U.S. Pat. No. 4,768,249 entitled "Patient Support Structure", Goodwin discloses a more conventional low air loss mattress formed of upright cells extending across the width of the bed.
Such mattresses as shown by Goodwin and Vrzalik are prone to bend or lean into an adjoining cell location when the adjoining cell is deflated. This tends to reduce the effectiveness of controlling the support pressure and location, which is necessary in the avoidance and treatment of bed sores, and also in the articulation of the bed.
It is also known to provide mattresses that have multiple layers. Grant, in U.S. Pat. No. 3,674,019 entitled "Dual Layer Cellular Inflatable Pad", describes a pad formed of offset layers of interdigitated inflatable sections. Welch, in U.S. Pat. No. 4,193,149 entitled "Beds and Mattresses", discloses a similar mattress, except the layer cells are aligned and separated by a preformed foam. Such mattresses assure resilient support for a patient, but provide limited control of support by adjacent cells.
Various cushions are also known for restraining a person. An elaborate example is disclosed by Boyce in U.S. Pat. No. 3,218,103 entitled "Pneumatic Restraint System". This patent discloses a chair having inflatable bands shiftable in position for selectively restraining a person. A restraining device that is releasably attached to a support platform for placement across the body of an infant is disclosed in U.S. Pat. No. 4,205,669 issued to Hamann for "Diaper-Changing Aid".
There thus remains a need for a means for restraining a person on a bed. In particular, it is desirable to have lateral cushions that conform to the sides of a person, and selectively inflatable cushions that are positionable over a person for keeping the person in the bed.